Soil standards

Sample Mean of four determinations/ fJg g l dry soil Standard deviation/ bgg Coefficient of variation, % Mean of four determinations/ fjg g dry soil Standard deviation/ fJgg Coefficient of variation % Difference/ bgg Standard error/fjg g l t... 

FIGURE 5.4 Some considerations in the prioritization of substances for the derivation of soil standards. 

Exposure models are a key tool in deriving SQSs for human health and environmental quality. These models should include all relevant soil processes and descriptions of human and animal behavior. Exposure models can be used to assess the likely spatial extent and severity of standard exceedance and provide input to prioritization of substances for which soil standards may be developed. 

Soil Quality Standards are developed for different purposes (e.g., different land uses and different protection goals) since soils are variable by nature and have various uses and functions that may influence the protection goals. Nevertheless, a minimum level of protection or a base level is needed to guarantee resilience of the soil ecosystem, and this should be incorporated into all approaches to soil standards. Standards can be derived that indicate the presence or absence of certain data. 

Upholstery and carpets are often treated with repellent finishes to minimize soiling during use. Since much of the soiling that occurs is due to dry soil, a test to evaluate dry soiling behavior is useful. AATCC Test Method 123-2000 can be used for upholstery and carpet samples. Either 10 g of actual vacuum cleaner soil or 10 g of a synthetic soil is rotated with pebbles in a rotary ball mill with two samples (3x7 inches) (7.6 x 18 cm) of the fabric to be tested. After a predetermined exposure time, the fabrics are removed, vacuumed and visually compared to previously soiled standards. 

Figure 1.2 Determination of lead in soil standard additions method.

Reported analysis of soil standard reference materials (IAEA Soil 5, IAEA SL-1 and BCR-141) indicate that about 16-20 elements may be determined with very good analytical characteristics in sediments and soils after introduction of background and spectral corrections (Liese, 1985a,b). Severson et al. (1992) reported the determination of 26 elements in soils. The accuracy and precision have been proven by analysis of NIST-SRMs. The concentration range varies between 0.1 (Se) p.g/g to %. Seventeen elements were reliably determined in soil and sediment standard reference materials without introducing any corrections (Kanda and Taira, 1988). 

Alvarez Fernandez, A., Garate, A., Lncena, J.J., 1997. Interaction of iron chelates with several soil materials and with a soil standard. J. Plant Nutr. 20, 559-572. 

Nutting, P.G. 1943. Soil standard thermal dehydration curves of minerals. United States Geological Survey, Professional Paper 197-E, Washington, DC, pp. 197-217. 

As seen in the specific examples given later, numerous analytical methods are used for the determination of uranium in environmental samples. The most popular among them are ICPMS and alpha spectrometry, but neutron activation analysis, gamma spectrometry, and XRF are often deployed and even simple spectrophoto-metric (like colorimetric aresnazo-III) techniques are sometimes still used. For the precise determination of total uranium and its isotopic composition, isotope dilution (ID) methods can be used. One example is a comparison of ID-TIMS and ID-SIMS for isotope ratios in soil standards where two separation and preconcentration chromatographic techniques were also compared (Adriaens et al. 1992). 

FIGURE 10.15 Acid-base titration curves of 14 humic substances, from IHSS standards Terrestrial FA samples are standard Elliot soil, standard Pahokee Peat and reference Pahokee Peat aquatic FA include standard Suwannee River, reference Suwannee River and reference Nordic Lake NOM is Suwannee River aquatic HA are standard Suwannee River and reference Nordic Lake and terrestrial HA include standard Elliot soil, standard Pahokee Peat standard Leonardite, reference Pahokee Peat and reference Summit Hill Soil (Reprinted frotri Geochimica et Cosmochimica Acta, 67, no. 1, Ritchie, J. D and Perdue, E Protonbindins study of standard and reference fulvic acids, humic acids, and natural organic matter 85-93 Copyright 2003, with permission from Elsevier.)... 

Standard Practice for Conducting and Evaluating Laboratory Corrosion Tests in Soils Standard Practice for Determining Rail-to-Earth Resistance... 

Smolders, E., K. Oorts, P. Van Sprang, et al. 2009. Toxicity of trace metals in soil as affected by soil type and aging after contamination Using cahbrated bioavaUability models to set ecological soil standards. Environ. Toxicol. Ghem. 28 1633-1642. 

Fig. 2.15 Recovery, over time, of ferulic (FER) acid (a P > 0.89) and vanillic (VAN) add (b) from sterile Cecil A and B soils by 0.25 M EDTA (pH 7) or water. Phenolic add added at time zero was 2.5 xmol/g soil. Standard error bars for (b) are smaller than the symbol representing the mean, a based on regressions and b based on data points of two figures from Blum et al. (1994). Plenum Publishing Corporation, regressions and data used with permission of Springer Sdence and Business Media...

Average individual phenolic acids for the wheat stubble/soybean 0-2.5 cm soil samples for the 109-day-experimental period were as follows p-coumaric acid 4.08 0.22, vanillic acid 2.06 0.11, syringic acid 1.53 0.07, p-hydroxybenzoic acid 1.51 0.06, caffeic acid 1.30 0.06, ferulic acid 1.21 0.08, sinapic acid 0.06 0.07, and total (sum of 7) 12.30 0.58 ug/g soil standard error (Figs. 3.8 and 3.9). Similar patterns, but lower concentfations, were observed for wheat stubble tilled under/soybean and fallow/soybean soil samples (Fig. 3.9). In... 

AIB-Vingotte International has a biodegradable home compost test certification for plastic products that references EN 13432 performance specification and other ISO biodegradable test methods. Biodegradation in soil environments is based on International OK Biodegradable Soil standards. Table 8.7 lists the biodegradation standards for home composing. 

In general, for soil, it can be noted that disintegration is largely determined by the intended use. For some applications, the plastic product should preferably disintegrate after a few months, while for other applications the product should remain intact for much longer. Consequently, many experts share the opinion that disintegration requirements should not be included in a soil standard. 

In Chapter 3, a variety of standard plots is presented. It is instructive to plot these as x plots to see how weU they obey the analytical expression. In the following, the x plot fits will be performed only on original data where available. Creation of the standard plot by some fitting routine or simply using a manual spline fit is in itself a distortion of the data. Indeed, the tho-ria and lunar soils standard plots were created using the insights of the x plot, so the standard plot by definition must fit the x plot perfectly. Similar problems are encountered in analyzing heat of adsorption. 

Standards are essential to ensure the environmental safety of compost. Hydrocarbon plastics do not biodegrade rapidly in compost or in soil and it must be demonstrated that, like of nature s wastes, they do not accumulate in the soil. Standards for biodegradability and compostability of plastics must therefore address, not only the question of non-accumulation of any long-lasting plastics residues in the soil substances but also the safety of any non-degradable residues. These aspects will be discussed in the light of recent scientific studies. 

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